It is sometimes desirable to detect characteristics of ink drops ejected by an inkjet printer. Characteristics of the ink drops may be used to assess the state or “health” of structural and operational features of the printer. For example, detecting that ink drops are absent where they should be present and detecting the number, size and/or shape of ink drops may help determine whether orifices through which ink drops are ejected (or are supposed to be ejected) are partially or fully clogged.
The same part numbers designate the same or similar parts throughout the figures.